Locking devices for hopper car doors



Sept. 22, 1964 T. MADLAND 3,149,582

LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 1 lil N]! 1- /N vE/v T0?- THoz Wu. 0 M9 D1. FIND '2 HTT V'I- Sept 22, 1964 T. MADLAND 3,149,582 LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 2 IN VE N TOE-\- THoe vnw Me DL 9ND P 22, 1964 T. MADLAND 3,149,582

LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 v 8 Sheets-Sheet 3 1 INVEN TOE-I- THORVHLO Meow/w:

p 2, 1964 T. MADLAND v 3,149,582

' LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 4 "I-INVENTO21- THoeveLo Mflac HMO Sept. 22, 1964 T. MADLAND 3,149,582

LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 5 p 2, 1964 'r. MADLAND 3,149,582

LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 6 INVEN TOR. THO/awn a Mam AND BY 9 m p 22, 1954 T. MADLAND 3,149,582

LOCKING DEVICES FOR HOPPER CAR DOORS Filed March 23, 1961 8 Sheets-Sheet 7 INVENTOR.

THOEVHLD MHDLQMD Sept. 22, 1964 T. MADLAND LOCKING DEVICES FOR HOPPER CAR DOORS 8 Sheets-Sheet 8 Filed March 23, 1961 IN VEN TOR. Mom/m0 Mam/2N0 United States Patent ration of Ohio Filed Mar. 23, 196i, Ser. No. 1916M? 29 Claims. (Cl. 105-=-253) This invention relates to locking devices for hopper car doors.

It is an object of this invention to provide individual locking devices for the doors which close the sloping hoppers of railway freight cars and which are'hinged at the top and swing downward and away from the hoppers to permit discharge of the material in the cars.

A further object is to provide locking devices for top hinged doors of hopper cars capable of locking the doors in both partly closed and fully closed positions and which shall be capable of swinging the doors from partly closed to fully closed position.

A further object is to provide locking devices for top hinged hopper car doors which shall be capable of imparting a positive opening thrust to the doors as the locking devices are released from the doors in the event that the latter do not swing open under their own weight or the weight of the load against them.

A further object is to provide locking devices for top hinged hopper car doors wherein the doors shall when swung in closing direction effect positive action of the locking devices to hold the doors in partly closed position.

A further object is to provide locking devices for top hinged hopper car doors of the character described immediately above which shall include safety means adapted to cooperate to secure the doors in partly closed position in the event that the locking devices are not successful in maintaining the doors in such position.

A further object is to provide locking devices for swinging hopper car doors which shall embody cam latches adapted to be restored to latching position upon actuation of the locking devices to release the doors.

A further object is to provide locking devices for top hinged hopper car doors which shall contain relatively few parts of economical and simple construction and which shall be easily operable.

A further object is to provide locking devices for swinging hopper car doors which shall be so constructed as to prevent accidental movement of the doors in opening direction.

Other objects of the invention will become clear as the description thereof proceeds.

In the drawings forming part of this specification:

FIG. 1 is an elevation partiy in section of a portion of a hopper car embodying the instant invention.

FIG. 2 is an elevation of a portion of a hopper car showing a hinged hopper door in closed position and parts of the locking device therefor.

FIG. 3 is a bottom plan view of a portion of a hopper car looking at a slope sheet of a hopper to which a locking device embodying the instant invention is secured.

FIG. 4 is a vertical section taken on line 44 of FIG. 3 showing the door disengaged from its locking member.

FIG. 5 is a view similar to FIG. 4 showing the door in partly closed position and engaged with its locking member.

FIG. 6 is a view similar to FIG. 4 showing the door fully closed and locked.

FIG. 7 is an end view looking toward the right in FIG. 3 showing the position of the cam latch and the cooperating teeth carried by the shaft of the locking device when the door is in the position similar to that shown in FIG. 4.

3,149,532 Patented Sept. 22., 1964 "ice FIG. 8 is a view similar to FIG. 7 showing the relationship between the cam latch and the cooperating teeth when the door is in partly closed position.

FIG. 9 is a view similar to FIG. 7 showing the locking relationship between the cam latch and the socket member mounted on the shaft of the locking device when the door is fully closed.

FIG. 10 is a vertical section similar to FIG. 4 showing a modified form of the invention.

FIG. 11 is a view similar to FIG. 10 showing the door partly closed.

FIG. 12 is a view similar to FIG. 10 showing the door fully closed.

FIG. 13 is a view similar to FIG. 3 showing another form of the invention.

FIG. 14 is a vertical section taken on line 1414 of FIG. 13 showing the door open and disengaged from the locking member.

FIG. 15 is a view similar to FIG. 14 showing the door partially closed and engaged with the locking member.

FIG. 16 is a view similar to FIG. 14 showing the door closed and locked.

FIG. 17 is an end view looking toward the right in FIG. 13 showing the door and disengaged from the looking member and the'cam latch supported by a ledge on the socket member.

FIG. 18 is an end view looking toward the right in FIG. 17.

FIG. 19 is a view similar to FIG. 17 showing the door partially closed.

FIG. 20 is an end view looking toward the right in FIG. 19.

FIG. 21 is a View similar to FIG. 17 showing the door closed.

FIG. 22 is an end view looking toward the right in FIG. 21.

N83. 23 and 24 are sectional views showing the co action of the cam and locking member to force the door to swing open in the event it is-frozen to the door frame.

FIG. 25 is an end view looking toward the right in FIG. 13 showing the means for adjusting the locking memher for proper engagement with the door.

Referring first to the embodiment of the invention illustrated in FIGS. 1 to 9, inclusive, the reference numeral 16 designates a portion of a hopper car which generally is of well-known construction. The hopper car 10 embodies the usual ridge sheets, one of which is shown at 11 which cooperate in the customary manner with side sheets such as 12 and slope sheets 13 to provide a plurality of hoppers 14 having discharge openings 15. It is well understood by those skilled in this art that the hoppers referred to above lie on opposite sides of the center sill 16 and extend substantially from the center sill to the sides of the car.

A hopper door frame indicated generally by the reference numeral 17 is secured to the ridge sheets 11 and the side and slope sheets 12 and 13 around the discharge openings 15. The discharge openings are adapted to be closed by hopper doors 18 which as is more clearly shown in'FIG. l of the drawings are hinged at their upper ends to the hopper door frame 17 as shown at 19. When closed the doors 18 lie in an inclined position as shown in FIG. 1 of the drawings and when open they hang vertically from their hinges as shown in dot and dash lines in this figure.

The instant invention provides a simple and economical locking device for retaining the doors in closed position and for insuring opening movement of the doors. In the considered form of the invention the locking device embodies a member 20 preferably in the form of a casting which is secured as by means of rivets 21 to the slope sheet contiguous with the lower portion of the hopper 3 door frame 17. As shown in FIG. 3 of the drawings the casting 20 projects beyond the outer side sheet 12 of the hopper and serves as a bearing for a shaft 22. A socket member 23 is mounted on the outer end of the shaft 22 and is adapted to receive a bar so that rotation can be imparted to the shaft.

A member 24 which may be a casting is secured to the slope sheet 13 approximately midway between the side sheets 12 in contiguous relationship with the lower portion of the hopper door frame. The casting 24 is formed with spaced flanges 25 within which the inner end of the shaft 22 is journalled as shown in FIG. 3 of the drawings.

A cam 26 is fixed upon the shaft 22 for rotation therewith and lies between the flanges 25 of the casting 24. A locking member 27 is rotatably mounted between the flanges 25 by means of a pin 2% which lies below the shaft 22. As is more clearly shown in FIGS. 4, and 6 of the drawings the locking member 27 is provided with spaced arms 29 and 39 of unequal length. The inner surface of the longer arm 29 is provided with a raised portion or projection 29a more clearly shown in FIG. 6 of the drawings which is adapted to cooperate with the cam 26 for a purpose which will hereinafter appear. The cam 26 is disposed in the space between the arms of the locking member 27. The latter is also provided with a hook end 31 which lies below the pin 28 and beneath an anti-friction roller 32 which is rotatably mounted by means of a pin 33 between spaced flanges 34 and 35 formed on the locking member 27. It will be clear from PEG. 4 of the drawings that the relationship between the hook end 31 and the anti-fric tion roller 32 provides a space 36 within which the depending lip 37 of a detent member 38 secured to the lower portion of the hopper door 18 is adapted to be received when the door is in partly closed and fully closed positions as shown in FIGS. 5 and 6.

The instant invention embodies means for retaining the door in the fully closed position shown in FIG. 4 of the drawings. For this purpose a cam latch 33 is pivotally mounted upon the member 20 as by means of a rivet 40. The cam latch 39 is thereby mounted for swinging movement in a vertical plane and in the fully closed position of the door engages the socket member 23 to retain the door in such position. The cam latch 39 is provided with an outwardly extending finger grip 41 and an inwardly extending stop member 4-2 which is adapted to cooperate with the member 20 to limit counterclockwise swinging movement of the cam latch.

The instant invention also provides a plurality of spaced teeth 43 and 44 which preferably constitute a portion of the socket member so that they rotate with the shaft 22. The teeth 43 and 44 as hereinafter explained are adapted to cooperate with the cam latch 39 to prevent undesired rotation of the shaft 22 when the door 18 is in partly closed position. The tooth 44, moreover, cooperates with a tooth 45 provided on the cam latch 39 in a manner which will be explained in the description of the operation of the instant locking device in order to insure locking engagement between the cam latch 39 and the socket member 23 when the door is fully closed.

The embodiment of the locking device illustrated in FIGS. 10, 11 and 12 of the drawings utilizes a latch member 46 which is materially smaller in size and simpler in construction than the locking member 27 or" the above described embodiment of the invention. In common with the locking member hereinabove described the locking member embodies spaced arms 47 and 48 between which a cam 49 of modified construction is adapted to be received. The arms 47 and 48 rise above the pivot pin 28 of the latch member. The latter also embodies a hook end 50 and an anti-friction roller 51 spaced from the hook end 50 and rotatably mounted on the locking member by means of a pin 52. A space 53 is thus pro 4 vided between the hook end 50 and the roller 51 adapted to receive the lip 37 of the detent 33 which is secured to the door.

The cam 49 is formed with an undercut portion which provides a shoulder or latch 54 which is shown in FIG. 10 of the drawings is adapted to lie upon the upper edge of the arm 4'7 of the locking member when the door has been fully disengaged from the locking member. Because of the modification of the shape of the locking member 46 and of the cam 49 a corresponding change in the form of the member 24 occurs. The member 55 which corresponds to the member 24 of the first embodiment of the invention and which is illustrated in FIGS. 10 to 12, inclusive, maintains spaced flanges 56 similar to the spaced flanges 25 of the member 24. The locking member 46 and the cam 49 are disposed between the flanges 56 in the same manner as the locking member 27 and the cam 26 are disposed between the flanges 25 of the member 24.

In addition to reduction in size and simpiification of parts the locking device of the considered embodiment of the invention permits the elimination of the cam latch 39 and the teeth 43 and 44 of the first considered embodiment of the invention. Moreover the raised portion 29a formed on the locking member 27 is eliminated.

Referring to the first described embodiment of the invention, to open the door 18 from its closed position shown in FIG. 6 to its open position shown in FIG. 4, the cam latch 39 illustrated more specifically in FIGS. 7 to 9, inclusive, is swung counterclockwise as viewed in FIG. 9 by means of the finger grip 41 until the stop member 42 engages the member 20. The cam latch is then supported by the member 21 as shown in dot and dash lines. A bar is then inserted into the socket member 23 and the shaft 22 and the cam 26 are rotated counterclockwise as viewed in FIG. 9. The teeth 43 and 44 also rotate counterclockwise and during such rotation the tooth 44 will engage the tooth 455 on the cam latch 39 and thereby swing the latter clockwise so that it can automatically engage and secure the socket member 23 against rotation when the door is fully closed. During this movement the portion of the cam which engages the longer arm of the locking member moves away from the latter permitting the locking member to swing in clockwise direction. If the door can at this time swing freely toward open position it will do so under its own weight and the weight of the load against it without any help or thrust from the cam as the locking member swings in a clockwise direction.

The clockwise swinging movement of the locking member 27 and the opening movement of the door will continue together until the lip 37 of the detent member 38 escapes from the hook end 31 of the locking member whereupon the door will wing to its full open position indicated in dot and dash lines in FIG. 1 of the drawings. The position of the locking member will then be as illustrated in FIG. 4 of the drawings and this position Will be maintained by the illustrated engagement between the longer arm 29 and the cam 26. To permit the indicated swinging movement and the illustrated relationship between the locking member 27 and the door 13 as shown in FIGS. 4, 5 and 6, the lower portion of the hopper door frame is coped, as indicated at 57.

However, as frequently occurs, particularly during cold weather, rotation of the shaft 22 and cam 26 may not be accompanied by a corresponding swinging movement of the locking member 27 and a swinging movement of the door in opening direction. When this occurs counterclockwise rotation of the shaft 22 will eflect engagement between the rear face of the cam 26 and the shorter arm 30 of the locking member so that the locking member will exert a positive thrust against the door compelling the latter to swing clockwise. If at this time the door is frozen to the hopper door frame so that it does not swing in opening direction under its own weight and the weight of the load within the hopper, the

roller 31?. will exert a positive thrust against the lip 37 of the detent member 38 thereby breaking the door away from the hopper frame and permitting it to swing to open position. Under either method of opening the hopper door, when the door is open the longer arm of the locking member 27 will bear against the cam 26 which serves to maintain the locking member in the proper position so that when the door is swung in closing direction it will strike the roller 32 to impart swinging movement in counterclockwise direction to the locking member.

The counterclockwise swinging movement of the locking member will effect engagement between the shorter arm 30 and the rear face of the cam 26 and will therefore cause the cam and the shaft 22 on which it is mounted to rotate in clockwise direction. At the same time the lip 37 of the detent member will enter the space 36 between the hook end 31 and the roller 32 of the locking member. The cam 26 will engage the longer arm 29 of the locking member as shown in FIG. 5 of the drawings and thereby prevent swinging movement of the locking member in clockwise direction. Consequently, the engagement between the hook end 31 of the locking member and the lip 37 will maintain the door in the partly open position illustrated in FIG. 5 of the drawings. At this time the cam 39 will lie in the path of movement or will engage the tooth 44 or as more often happens the tooth 43 and prevent rotation of the shaft and cam counterclockwise. This engagement serves to prevent swing ing movement of the locking member 27 clockwise and therefore disengagement of the lip 37 from the hook end 31 of the locking member. Securement of the door 18 in partly closed position is thereby insured.

To complete the movement of the door to fully closed position a bar is then inserted in the socket member 23 and the shaft 22 is rotated clockwise. During this rotation the cam 26 acts upon the longer arm 29 of the locking member causing it to swing counterclockwise. During this swinging movement of the locking member the hook end 31 through its engagement with the lip 37 produces swinging movement of the door 18 to closed position. When this has occurred the cam latch 39 engages the socket member 23 thus preventing rotation of the shaft and opening movement of the door.

When the door is in closed and locked position as shown in FIG. 6 of the drawings, the raised portion or projection 2% lies in the path of counterclockwise movement of the cam 26, that is, the direction in which the cam 26 would swing to'permit release of the locking member 27 from the door and swinging movement of the door to open position. This relationship between cam 26 and the projection 29a serves to prevent accidental or undesired counterclockwise rotation of the shaft 22 and swinging of the cam 26 which might be produced by vibration or impact to the car when the cam latch 39 has not been engaged with the socket member 23 or is not functioning properly. Should this rotation of the shaft and swinging of the cam occur, the cam will engage the projection and tend to swing the locking member in counterclockwise direction. This would tend to cause the locking member to swing the door in closing direction, a tendency resisted by the engagement of the door with the door frame 17. Therefore, the locking member is restrained by the door from swinging counterclockwise and the cam consequent- 1y cannot pass by the projection. Since the cam is thus restrained by the projection from swinging in counterclockwise direction, the shaft on which it is mounted cannot rotate in this direction and engagement between the cam and the projection on the locking member is maintained. Accidental or undesired opening of the door is thereby prevented. Similarly accidental or undesired opening of the door is prevented when it is in the partially closed position shown in FIG. 5. The raised portion or projection 29a lies in the path of counterclockwise movement'of the cam 26; If such movement of the cam should tend to occur the cam will engage the projection and tend to swing the locking member counterclockwise. This tendency of the locking member would be resisted by the weight of the door and the load upon it. The cam, consequently, cannot pass by the projection, the shaft cannot rotate and the door cannot accidentally swing to open position.

To open the door shown in connection with the embodiment of the invention'illus-trated in FIG. 10, 11 and 12 of the drawings a baris inserted in the socket member 23 which in this embodiment is also secured to the end of the shaft 22 and the shaft and cam are rotated clockwise as viewed in FIG. 10. If the door and the locking member 46 are free to swing during this rotation of the shaft and the cam 49 the locking member 46 will swing clockwise about the pin 28 so that the lip 37 will become disengaged from the hook end 5t) of the locking member and the door will under its own weight and the weight of the material in the hopper swing to full open position. At this time, as shown more clearly in FIG. 10 of the drawings, the upper edge of the longer arm 47 of the lock- 7 ing member will be positioned under the shoulder 54 of the cam 49 and its inner face will bear against the cam adjacent to the shaft 22. The cam thereby serves to retain the locking member in position so that when the door is swung in closing direction engagement between the lip 37 on the door and the roller 51 on the locking member is insured.

When this engagement occurs during swinging movement of the door in closing direction counterclockwise swinging movement of the locking member will be pro duced. During this movement the upper edge of the longer arm 4'7 of the locking member will move out from under the shoulder 5'4 of the cam 49 and the shorter arm 48 of the locking member will strike and impart counterclockwise rotation to the cam 49 and the shaft 22. This action brings about the engagement between the cam 49 and the longer arm 47 of the locking member illustrated in FIG. 11 of the drawings so that engagement between the hook end 50 of the locking member and the lip 37 which has occurred during this action will maintain the door in the partly closed position illustrated in FIG. 11 0f the drawings. The structure and relationship of the locking member and the cam is such that no additional means is required to insure retention of the door in the partly closed position.

Thereafter a bar is inserted in the socket member 23 and counterclockwise rotation is imparted to the shaft 22 and the cam 49. The relationship between the cam and the longer arm 47 is such that during this rotation counterclockwise swinging movement is imparted to the locking member 46 which causes the door to move to the fully closed position shown in FIG. 12 of the drawings. The aforementioned structure and relationship of the locking member and the cam is such that the engagement between them securely retains the door in its fully closed position without the need of a cam latch or other latching means.

The locking mechanism illustrated in FIGS. 10, 11 and 12 of the drawings is also effective to impart a direct thrust to the locking member 46 and through it to the 4 door 18 in the event that either or both of these parts are frozen. With reference to FIG. 12 of the drawings it will be seen that as the cam rotates clockwise it will in the event that the locking member and the door cannot swing freely bear against the shorter arm 48 of the locking member so as to impart a positive thrust to the locking memher and force it to swing clockwise. swing freely open as the locking member swings clockwise, the roller 52 carried by the locking member will bear against the lip 37 of the door and impart a positive thrust to the latter forcing it to swing open.

In the form of the invention illustrated in FIGS. 13 to 25 the locking member is constituted as a complete unit which is secured as such to the hopper by welding it to If the door does not the slope sheet 13 and to the hopper door frame 17. This unit embodies a base 58, preferably in the form of a channel member 59 having a web dd and outturned flanges 61 and 62, to which the shaft supporting brackets 63 and 64 are secured as by welding.

The bracket 63 is formed with a bearing member 65 in which the outer end of the shaft 22 is journalled. The bracket 63 also carries outwardly projecting spaced ears 6 and 67 between which a cam latch 68 is pivotally mounted to swing transversely of the car. The bracket 64 is formed with spaced flanges69 and 70 in which the inner end of the shaft 22 is journalled.

A socket member 71 is welded upon the outer end of shaft 22. A bar is inserted in the socket member and turned to impart rotation to the shaft. The socket member is adapted to be engaged by the cam latch 68 to prevent rotation of the shaft.

A cam 72 is mounted upon the inner end of shaft 22 for rotation therewith and is disposed between the flanges 69 and '70 of bracket 64-. Cam 72 is formed with angularly related faces 73 and 74 and is adapted to cooperate with a locking member 75 which lies in the path of movement of cam 72 and which is swingably mounted upon a pin 76 supported by the flanges 69 and 7d in spaced relationship to the shaft 22. Cam 72 is also provided with a lug 77 which is engageable with the flange 61 to limit rotation of the cam in one direction. Flange 61 is notched as shown at 78 to permit the desired rotation of the cam.

The locking member 75 is provided with a hook end 79 which lies below the pin 76. The locking member carries a projection hit in line with the hook end 79 and related thereto so as to provide a space 83. within which a portion of the detent member 82 is received when the door 18 is retained in closed or partially closed position by the locking member.

The locking member also has spaced arms 83 and 84 which extend beyond and on opposite sides of the pin 76. The cam 72 is received in the space between the arms. The arm 83 is formed with a raised portion or projection 85 which is adapted to cooperate with the cam 72 as hereinafter explained.

It is apparent from the foregoing that the locking device of the instant invention constitutes a complete unit which is secured to the hopper as a unit. The elements of the locking device are mounted upon the base 58 which is seated upon the hopper door frame 17 and welded thereto and to the slope sheet 13, thereby accurately and quickly mounting the locking device.

The relationship between the cam 72 and the locking member 75 and between the socket member '71 and the cam latch 63 when the door is in closed position is illustrated in FIGS. 21 and 22. To open the door the cam latch 6% is raised and released from the socket member 71. Movement of the cam latch is aided by the provision of lugs 86 and 87 which project from the cam latch. A bar is inserted in the socket member 71 and swung clockwise as viewed in FIG. 21. parted to the shaft 22 and the cam 72 mounted thereon until the lug 77 engages the flange d1 of the base member and further rotation is prevented. At this time as shown in FIG. 14, the unpper end of arm 3-3 is disposed under the shoulder 88 formed on the cam which is engaged by this arm, and the locking member is released from the door. If the door is free to swing it will swing to open position and the load in the car will be discharged through the hopper. The engagement between arm 83 and cam 72 will maintain the locking member in this position.

However, if the door is frozen to the door frame 17 the locking member 75 will swing clockwise as viewed in FIG. 23 until the projection 89 engages the detent 82. Continued rotation of the shaft 22 causes the cam 72 to engage the arm 84- of the locking member whereupon a thrust may be exerted against the arm 34 by the bar acting through the cam. This thrust is transmitted to the detent by the projection so that the door is broken away Rotation is thus im-.

from the door frame and forced to swing toward open position as shown in FIG. 24. Upon release of the door from the locking member the latter will swing to the position shown in PEG. 14.

The socket member 71 is formed with a ledge 89 which when the door is closed is remote from the cam latch 68. As the socket member is turned the ledge swings upward and when the door is released from the locking member engages the cam latch to prevent it from swinging down behind the socket member. The cam latch is thereby prevented from engaging the socket member and interfering with the counterclockwise rotation of the shaft and cam as viewed in FIG. 17 and automatic locking of the door in partially closed position. With the cam latch supported upon the ledge the shaft and cam are free to rotate counterclockwise. When the door is swung in closing direction the detent will strike the projection 3% on the locking 'member producing counterclockwise swinging of the locking member. Arm 83 will move out from under shoulder 3 and arm 84 will strike the cam 72 causing it and shaft 22 to rotate counterclockwise and establish the engagement between the cam and arm 83 shown in FIG. 15. The detent has now moved into the space 31 and is engaged by the hook end 79 of the locking member, locking the door in partially closed position.

To complete closing of the door a bar is inserted in the socket member and the shaft and cam are rotated counterclockwise as viewed in FIG. 15. The cam pro duces counterclockwise swinging of the locking member which pulls the door closed. The latch cam 68 is then engaged with the socket member 71 as shown in FIGS. 21 and 22 and the door is locked.

PEG. 15 illustrates the relationship between the cam 72 and the projection 35 formed on the locking member whereby accidental opening movement of the door from its partially closed position is prevented. The projection lies in the path of movement of the cam. In the partially closed position of the door the end portion 98 of the cam face 74 lies below the projection. Thus, any tendency of the shaft and cam to accidentally rotate clockwise as viewed in FIG. 15 and effect release of the cam from the locking member and opening of the door is resisted by the projection 85. Tendency of the cam 72 to rotate clockwise would, because of the projection 85, tend to cause the locking member 75 to swing counterclockwise. Since the door bears against the hook end 79 of the locking member hook end would tend to swing the door closed. This tendency is resisted by the weight of the door and the weight of the load bearing against it. Clockwise rotation of the shaft 22 and the cam 72 is prevented and the engagement between the cam and locking member shown in FIG. 15 is maintained. The door, therefore, cannot swing open.

Similarly, accidental disengagement of the cam from the locking member and opening movement of the door is prevented when the door is closed, if the latch cam is not in locking engagement with the socket member. Here the inner end of the cam face 73 lies in the path of and below the projection 85. Any tendency of the shaft and cam to accidentally rotate clockwise as viewed in FIG. 16 and become disengaged from the locking member so that the door can swing open is resisted by the projection. If the cam were to swing clockwise the inner end of cam face 73 would engage the projection 85 on the locking member and tend to swing the locking member counterclockwise. Since the hook end of the locking member bears against the door the locking member tends to swing the door in closing direction. The door, however, bears against the door frame and cannot swing in closing direction. Consequently, the cam cannot rotate clockwise and the door is maintained in closed position even if the cam is in raised position.

To insure engagement of the locking member 75 with the door so that it will draw the door into locked engagement with the door frame the locking member is mounted in such a manner that it can be shifted toward or away from the door frame. To this end the pin '76 is formed with an eccentric portion 91 on which the locking member is mounted. A member 92 is welded upon the inner end of pin '76 as indicated at 93 restricting this member for rotation with the pin. An arcuate flange 94 extends from the inner end of member $2; in adjacent and concentric relationship with an arcuate flange 5 formed on flange 76 of bracket 64. Spaced openings $6 are formed in arcuate flange 94. A larger number of spaced openings 97 are formed in flange 95.

In FIG. 25 of the drawings one position of the locking member 75 is shown in full lines. This position is maintained by a cotter pin 98 which passes through openings 96 and 97 that are alined. However, if in this position the locking member is not effective to lock the door in engagement with the door frame and it becomes neces sary to shift the locking member relative to the frame the cotter pin is withdrawn and the member 92 rotated thereby rotating the pin 76. As the eccentric portion 91 of the pin rotates it moves the locking member relative to the door frame, the amount of such movement depending upon the angular displacement of the member 92. When the proper position of the locking member has been determined it is maintained by passing the cotter pin through openings 96 and 97 which are in register.

This application is a continuation in part of application Serial No. 685,009, filed September 19, 1957.

It will be apparent that numerous changes and modifications in the details of the invention will be clear to those skilled in the art. It is intended, therefore, that all such modifications and changes be comprehended within this invention which is to be limited only by the scope of the claims appended hereto.

I claim:

1. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam ec centrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one ofsaid brackets in the path of said cam, said cam engaging said locking member and imparting swinging movement thereto in one direction upon rotation of said shaft, said hook end of said locking member engaging said door during said swinging movement of said locking member to impart swinging movement to said door to close said door, said cam engaging said locking member to prevent swinging movement of said locking member in the opposite direction and swinging movement of said door.

2. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured tosaid sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said hook end engaging one side ofsaid door when said door is closed, said cam engaging said locking member and imparting swinging movement thereto upon rotation of said shaft, said locking member engaging the other side of said door upon said swinging movement and forcing said door to swing in opening direction.

3. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wail adjacent to the discharge opening, a shaft journalled in said bracket, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, means spaced below said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said hook end lying below said mounting means, said locking member extending above said mounting means, said cam being engageable with a portion of said locking member above said mounting means to impart swinging movement thereto in one direction upon rotation of said shaft, said hook end of said locking member engaging one side of said door during said swinging movement of said locking member to impart swinging movement to said door to close said door, said cam being engageable with another portion of said locking member above said mounting means to impart swinging movement thereto in the opposite direction upon rotation of said shaft, said locking member engaging the other side of said door during said latter swinging movement to force said door open.

4. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentricaily mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said door hanging vertically when open, a portion of said locking member above said hook end lying in the path of said door, said door striking said portion of said locking member when said door is swung toward closed position and producing swinging movement of said locking member in one direction, said locking member during swinging movement striking said cam and effecting rotation of said cam and shaft, said cam upon rotation thereof engaging said locking member and preventing swinging movement thereof in the opposite direction, said hook end engaging said door and retaining said door in partly closed. position.

5. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a'shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end and a portion eX- tending beyond said hook end in spaced relationship thereto and providing a door receiving recess therewith, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said door hanging vertically when open,

said door striking said extending portion when said door is swung toward closed position producing swinging movement of said locking member, said locking member during swinging movement thereof striking said cam and edecting rotation thereof, said cam during said rotation engaging said locking member and preventing swinging movement thereof in the opposite direction, said door being received in said recess, said hook end engaging said door and retaining said door in partly ciosed position.

6. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith,

a locking member having a hook end and a bifurcated portion extending beyond said hook end in spaced re lationship thereto and providing a door receiving recess therewith, a roller mounted in said bifurcated portion, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said door hanging vertically when open, said door striking said roller when said door is swung toward closed position producing swinging movement of said locking member, said locking member during swinging movement thereof striking said cam and effecting rotation thereof, said cam during said rotation engaging said locking member and preventing swinging movement thereof in the opposite direction, said door being received in said recess, said hook end engaging the underside of said door and retaining said door in partly closed position.

7. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in cooperative relationship with said cam, said shaft projecting beyond the other of said brackets, means on said shaft projection whereby said shaft can be rotated, and a cam latch mounted on said other bracket adapted to engage said last mentioned means to prevent rotation of said shaft when said door is closed.

8. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced bracket secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets, said hook end engaging said door and said cam engaging said locking member to lock said door in closed position, said shaft projecting beyond the other of said brackets, a member on said shaft projection having a tooth, a cam latch swingably mounted on said other bracket, a tooth and a stop on said latch, said latch engaging said shaft projection to prevent rotation of said shaft when said door is closed, said latch being swingable away from said shaft projection prior to opening movement of said door, said stop engaging said other bracket to limit swinging movement of said latch, said tooth on said member engaging said tooth on said latch during rotation .of said shaft to release said hook end from said door to swing said latch to position for engagement with said shaft projection when said door is closed.

9. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam engaging said locking member and said hook end engaging said door to hold said door in partly closed position, said shaft projecting beyond the other of said brackets, a member on said shaft projection having a tooth, and a cam latch swingably mounted on said other bracket, said tooth on said member engaging said cam when said door is in partly closed position to prevent rotation of said shaft and open ing movement of said door.

'10. in a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, said cam having a shoulder, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam engaging said locking member and imparting swinging movement thereto upon rotation of said shaft in one direction, said hook end engaging said door during said swinging movement to close said door, said cam engaging said locking member to prevent swinging movement of said locking member in the opposite direction and swinging movement of said door, said shaft and cam being rotatable in the opposite direction to release said locking member for swinging movement and disengagement of said hook end from said door, a portion of said locking member lying under said shoulder in engagement with said cam when said door is disengaged from said hook end.

11, In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, said cam having a shoulder, a locking member having a hook end and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam being engageable with said locking member to impart swinging movement thereto and effect disengagement of said hook end from said door upon rotation of said shaft, a portion of said locking member lying under said shoulder and in engagement with said cam when said hook end is disengaged from said door.

12. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said sloping Wall adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member and means spaced from said shaft svtringably mounting said locking member on one of said brackets in the path of said cam, said cam being engageable with said locking member and imparting swinging movement thereto upon rotation of said shaft in one direction, said cam being engageable with said locking member and imparting swinging movement thereto in the opposite direction upon rotation of said shaft in said opposite direction.

13. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam being engageable with said locking member and imparting swinging movement thereto upon rotation of said shaft, said shaft projecting beyond the other of said brackets, means on said projecting portion of said shaft whereby 3 said shaft can be rotated, and a latch mounted on said other bracket, said latch being engageable with said last mentioned means to prevent rotation of said shaft.

14. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member and means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam being engageable with said locking member and imparting swinging movement thereto upon rotation of said shaft, said shaft projecting beyond the other of said brackets, means on said projecting portion of said shaft whereby said shaft can be rotated and a la-tch'pivotally mounted on said other bracket, said latch having a stop and a tooth and being engageable with said last mentioned means to prevent rotation of said shaft.

15. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said lockingdevice comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member and means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam being engageable with said locking member and imparting swinging movement thereto upon rotation of said shaft, said shaft projecting beyond the other of said brackets, means on said projecting portion of said shaft whereby said shaft can be rotated, a tooth on said projecting portion of. said shaft, and a latch pivotally mounted on said other bracket, said latch having a stop and a tooth and being engageable with said last mentioned means to prevent rotation of said shaft.

16. The combination as defined in claim 1 wherein said cam is undercut to provide a shoulder.

17. The combination as defined in claim 3 wherein said cam is undercut to provide a shoulder and one of said arms lies under said shoulder in engagement with said cam when said locking member is released from said door.

18.- In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam engaging said locking member and imparting swinging movement thereto in one direction upon rotation of said shaft,- said hook end of said locking member engaging said door during said swinging movement of said locking member to impart swinging movement to said door to close said door, said locking member having a projection lying in the path of said cam, said projection engaging said cam to prevent undesired release thereof from said locking member and disengagement'of said locking member from said door when said door is closed.

19. In a railway car having a hopper provided with a sloping bottom wall and an inclined discharge opening and a door hinged at its upper end to the car above the discharge opening for closing the discharge opening, a locking device for said door comprising spaced brackets secured to said sloping wall adjacent to the discharge opening, a shaft journalled in said brackets, a cam ec centrically mounted on said shaft for rotation therewith, a locking member having a hook end, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said door hanging vertically when open, a portion of said locking member above said hook end lying in the path of said door, said door striking said portion of said locking memher when said door is swung toward closed position and producing swinging movement of said locking member in one direction, said locking member during swinging movement striking said cam and eifecting rotation of said cam and shaft, said cam upon rotation thereof engaging said locking member and preventing swinging movement thereof in the opposite direction, said hook end engaging said door and retaining said door in partly closed position, said locking member having a projection lying in the path of said cam, said projection engaging said-cam to prevent undesired release thereof from said locking member and disengagement of said locking member from said door when said door is partly closed.

20. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom Wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said bottom wall adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam engaging said locking member when said locking member engages said door to hold said door in closed position, said locking member having a projection, said projection lying in the path of said cam and being engageable therewith to prevent undesired release thereof from said locking member and disengagement of said locking member from said door when said door is closed.

21. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said bottom wall adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, and means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam engaging said locking member when said locking member engages said door to hold said door in closed position, said locking member having an arm lying on one side of and extending above the axis of said mounting means, a projection on said arm, said projection lying in the path of said cam and being engageable therewith to prevent undesired release thereof from said locking member and disengagement of said locking member from said door when said door is closed.

22. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said bottom wall adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, means spaced from said shaft swingably mounting said locking member on one of said brackets, one part of said cam engaging said locking member when said locking member engages said door to hold said door in partly closed position, another part of said cam engaging said locking member and said locking member engaging said door to hold said door in closed position, said locking member having a projection, said projection lying in the path of said cam and engaging said one part of said cam to prevent undesired release thereof from said locking member and disengagement of said locking member from said door when said door is partly closed, said projection engaging said other part of said cam to prevent undesired release thereof from said locking member and disengage ment of said locking member from said door when said door is closed.

23. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said bottom wall adjacent to the lower edge thereof, a shaft extending between and journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, and means spaced from said shaft swingably mounting said locking member on one of said brackets, said cam engaging said locking member when said locking member engages said door to hold said door in closed position, said locking member having spaced arms tying on opposite sides of said shaft and on the same side of said mounting means, a projection on one of said arms, said projection lying in the path of said cam and being engageable therewith to prevent undesired release thereof from said locking member and disengagement of said locking member from said door when said door is closed, said other arm lying in the path of said cam and being engaged thereby upon rotation of said cam in the opposite direction to exert pressure upon said locking member to force the latter against said door and effect opening movement thereof.

24. A unit locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising a base member, spaced brackets secured to said base member, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith a locking member, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam.

25, The combination as defined in claim 24 wherein said base member is a channel and said brackets are secured to the web thereof between outwardly extending flanges thereof.

26. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft journaled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith, a locking member, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam being engageable with said locking member and imparting swinging movement thereto upon rotation of said shaft, said shaft projecting beyond the other of said brackets,

means on said projecting portion of said shaft whereby said shaft can be rotated, and a latch mounted on said other bracket, said latch being engageable with said last mentioned means to prevent rotation of said shaft, said last mentioned means having a ledge projecting therefrom, said ledge engaging said latch when said shaft has been rotated to permit release of said locking member from said door, said ledge maintaining said latch out of engagement with said last mentioned means.

27. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rota tion therewith a locking member, and means spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said cam engaging said locking member and imparting swinging movement thereto upon rotation of said shaft, said means comprising a pin provided with an eccentric portion, said locking member being mounted on said eccentric portion.

28. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft journalled in said brack ets, a cam eccentrically mounted on said shaft for rotation therewith a locking member, a pin spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said pin having an eccentric portion, said locking member being mounted on said eccentric portion, said cam engaging said locking member and imparting swinging movement thereto about said eccentric portion upon rotation of said shaft, said said pin projecting beyond said bracket, a member mounted on said projection for rotation with said pin, a flange extending from said member, a plurality of openings formed in said flange, a flange extending from said one bracket, a plurality of openings formed in said latter flange and means extending through selected openings in said flanges releasably securing said pin in desired relationship with said locking member.

29. A locking device for a door hinged at its upper end to a railway hopper car above a discharge opening in a hopper thereof having a sloping bottom wall, said door lying in inclined position to close the discharge opening, said locking device comprising transversely spaced brackets adapted to be secured to said slope sheet adjacent to the lower edge thereof, a shaft journalled in said brackets, a cam eccentrically mounted on said shaft for rotation therewith a locking member, a pin spaced from said shaft swingably mounting said locking member on one of said brackets in the path of said cam, said pin having an eccentric portion, said locking member being mounted on said eccentric portion, said cam engaging said locking member and imparting swinging movement thereto about said eccentric portion upon rotation of said shaft, means on said one bracket and on said pin, said means on said pin being selectively displaceable relative to said means on said one bracket to rotate said pin to desired position relative to said locking member, and a member releasably securing said means on said one bracket and on said pin together in said position of said pin.

References ited in the file of this patent UNIT ED STATES PATENTS 678,889 Mallory July 23, 1901 771,256 Lancaster Oct. 4, 1904 1,584,417 Wine May 11, 1926 1,584,418 Wine May 11, 1926 1,800,161 Smith Apr. 7, 1931 1,847,516 Knepper Mar. 1, 1932 2,482,516 Sheesley Sept. 20, 1949 2,684,645 Shaver et al. July 27, 1954 2,697,002 Johansson Dec. 14, 1954 

1. IN A RAILWAY CAR HAVING A HOPPER PROVIDED WITH A SLOPING BOTTOM WALL AND AN INCLINED DISCHARGE OPENING AND A DOOR HINGED AT ITS UPPER END TO THE CAR ABOVE THE DISCHARGE OPENING FOR CLOSING THE DISCHARGE OPENING, A LOCKING DEVICE FOR SAID DOOR COMPRISING SPACED BRACKETS SECURED TO SAID SLOPING WALL ADJACENT TO THE DISCHARGE OPENING, A SHAFT JOURNALLED IN SAID BRACKETS, A CAM ECCENTRACALLY MOUNTED ON SAID SHAFT FOR ROTATION THEREWITH, A LOCKING MEMBER HAVING A HOOK END, AND MEANS SPACED FROM SAID SHAFT SWINGABLY MOUNTING SAID LOCKING MEMBER ON ONE OF SAID BRACKETS IN THE PATH OF SAID CAM, SAID CAM ENGAGING SAID LOCKING MEMBER AND IMPARTING SWINGING MOVEMENT THERETO IN ONE DIRECTION UPON ROTATION OF SAID SHAFT, SAID HOOK END OF SAID LOCKING MEMBER ENGAGING SAID DOOR DURING SAID SWINGING MOVEMENT OF SAID LOCKING MEMBER TO IMPART SWINGING MOVEMENT TO SAID DOOR TO CLOSE SAID DOOR, SAID CAM ENGAGING SAID LOCKING MEMBER TO PREVENT SWINGING MOVEMENT OF SAID LOCKING MEMBER IN THE OPPOSITE DIRECTION AND SWINGING MOVEMENT OF SAID DOOR. 